Eyepiece Tele Vue Plossl 25mm 1.25" 52° apparent field

The Tele Vue Plossl 25mm 1.25" eyepiece offers a medium focal length solution for general astronomical observing. With a 52° apparent field of view and a classic four-element Plossl optical design, this eyepiece is intended for users who want a balanced image with good contrast, sharpness across most of the field, and reliable performance on lunar, planetary and many deep-sky targets depending on telescope focal length.

Advantages

This 25mm Plossl provides a comfortable exit pupil size on a wide range of telescopes, making it useful for extended observing sessions. The Plossl configuration delivers well-controlled aberrations and a neutral image contrast that is suitable for both high-contrast targets like the Moon and lower-contrast deep-sky objects. The 1.25" barrel format ensures compatibility with the majority of standard focusers and diagonal holders.

Suitable for

• Medium-power planetary observation
• Lunar viewing with good detail and contrast
• Wide-field deep-sky objects on longer focal-length telescopes
• General-purpose observing and outreach sessions

When it may not be suitable

The 52° apparent field is narrower than modern wide-field eyepieces, so it may feel restrictive to observers seeking very wide immersive views. Users requiring the widest possible fields for large nebulae or visual panoramas may prefer wide-angle or ultra-wide eyepiece designs. Very fast refractors or wide-field imaging applications may reveal edge softness compared with more complex, multi-element eyepieces.

Key specifications

• Focal length: 25 mm
• Apparent field of view: 52°
• Barrel diameter: 1.25" (31.7 mm)
• Optical design: Plossl (four-element symmetrical design)
• Intended use: visual astronomy

How to use

Insert the eyepiece into a 1.25" focuser or diagonal and secure it with the focuser thumbscrew. Start observing at low to medium magnification to locate the object and then adjust focus carefully for peak sharpness. For best results, allow the telescope to reach ambient temperature and use slow, small focus adjustments when observing planets or double stars. If using a finder or laser collimator, align the telescope first to make target acquisition faster.

What to consider before purchase

• Compatibility with your instrument's 1.25" focuser or diagonal
• Desired apparent field compared with wide-angle eyepieces
• Telescope focal length and the resulting magnification and exit pupil
• Portability and whether a single eyepiece meets your observing priorities

Usage recommendations

For balanced performance across lunar, planetary and many deep-sky targets, use the Tele Vue Plossl 25mm as a general-purpose eyepiece in your kit. Pair it with a finder and a lower- and higher-power eyepiece to cover a broad range of targets during a single observing session.